2025-2026 Audi Steering Fault TSB 2079733/4

Audi has released Technical Service Bulletin (TSB) 2079733/4 to address instances where the "yellow steering warning lamp" illuminates in the instrument cluster of certain 2025-2026 Audi A5, A6, and S5 models. This bulletin specifically targets a software-related issue that can lead to a Audi steering fault B200042 or other diagnostic trouble codes (DTCs) related to the steering system.

This TSB provides comprehensive guidance for technicians to diagnose and rectify the underlying software problem, ensuring the proper function of the steering system and resolving the warning lamp illumination. Owners experiencing this issue should be aware that a software update is the prescribed solution.

Symptoms

Owners of affected Audi vehicles may observe the following symptom:

• The "yellow steering warning lamp" lights up in the instrument cluster. This can occur while driving, during a software update process, or following a workshop visit.

Fault Codes / DTCs

When diagnosing the issue, technicians may find specific diagnostic trouble codes (DTCs) stored in the vehicle's system. However, the yellow steering warning lamp can also illuminate even without any stored DTCs.

Technical Background

The root cause of this steering fault is identified as a software issue. This problem stems from an internal memory layout optimization and a need for increased software robustness within the vehicle's control systems. Addressing this software deficiency is crucial for resolving the Audi steering fault B200042 and related warnings.

Repair Procedure Summary

The recommended repair involves performing a specific software update. Technicians are instructed to apply the software update detailed in TSB 2079690, which includes a